Welcome! So sad your kitty was gone and had such a rough time, but am glad to hear he is home.
You are in the right place to get help for him. There is a lot to take in, but there is decades of experience here with feline diabetes and a great support network. Vets will prescribe insulin, but rarely monitor our cats the way we do to ensure they are not on too high a dose and are getting what they need to live their best life with diabetes.
Going forward, you can post general health question to the main Health forum and you can post Prozinc specific questions to that forum.
I do know the DM regular wet is low carb, the selects wet is slightly higher, but the dry is very high carb for diabetics. Fancy Feast pates are good as long as no kidney issues, for that you need a lower phosphorus food. You want to be careful transitioning to lower carb and do it gradually, because it will bring blood sugar down some and then insulin normally would need to be decreased. There is guidance here on how to transition to all wet low carb.
Normally if diabetes is caught in first 6 months there is a higher success rate for remission, but I have heard still possible for longer term diabetics to achieve remission, but is harder when they have had it for a long time. Another insulin may be an option. I would say get some input from Prozinc users first before switching.
It is great you are home testing!!! One hurdle crossed! That is usually the hardest part for new diabetic pet parents.
Not knowing history on sugar levels etc, it is hard to say if your kitty is on a good dose currently. If you have had several hypos recently, chances are the dose may be too high for him.
If you would like some guidance on getting his diabetes better controlled, we use a spreadsheet here to keep track of blood sugar readings, insulin dose, etc. it helps the more experienced members here provide guidance if you need help for your kitty.
We take minimum of readings before am and pm shots. Other readings a few times during the day or before bed are helpful to better see how your cat is responding to insulin and if he is on the right dose. Depending on which insulin, there may be different suggested test times.
Here is how to get a spreadsheet set up. If you need help our resident spreadsheet expert can assist.
http://www.felinediabetes.com/FDMB/threads/fdmb-spreadsheet-instructions.130337/
http://www.felinediabetes.com/FDMB/threads/understanding-the-spreadsheet-grid.156606/
It also helps to set up a signature with pertinent info about your cat. That way every time you post anyone trying to help answer questions can see everything right there.
Setting up your signature (light grey text under a post). Here's how:
click on your name in the upper right corner of this page
click on "signature" in the menu that drops down
type the following in the box that opens: kitty's name/age/date of diabetes diagnosis/insulin you're using and dosage amount /glucose meter you're using/what (s)he eats/any other meds or health issues (s)he has. You can add your name, and a geographic location (sometimes the time zone matters) Be sure to SAVE when you are finished.